The Role of Eye-Movements in Eye-Movement Desensitization and Reprocessing: Eye-Movements Lower the Number of Intrusive Thoughts of Negative Memories
Eye-Movement Desensitization and Reprocessing (EMDR) was developed as a treatment for Post-Traumatic Stress Disorder (PTSD), and involves the patient thinking about a traumatic event while simultaneously moving their eyes from side to side. Despite substantial support for the efficacy of EMDR questions remain regarding how eye-movements contribute to therapy. One explanation is that eye-movements tax a part of working memory known as the central executive; however, the exact mechanism involved is still unclear. Previous eye-movement research has focussed on self-ratings of vividness and emotionality of negative memories as the primary outcome measures. The focus of the current research was to examine the effect of eye-movements on the suppression of negative autobiographical memories in addition to vividness and emotionality. Non-clinical participants were asked to recall negative autobiographical memories and then verbally reported ratings of vividness and emotionality. In the eye-movement conditions, which varied by speed and direction of movement, eye-movements were stimulated using dots on a computer screen. Participants were then asked to avoid thinking of their memories, and intrusive thoughts were measured by pressing a computer key. Six experiments found that, overall, the effect of eye-movements on self-ratings was inconsistent, but that eye-movements reliably improved suppression of negative autobiographical memories. The findings also support the central executive explanation for the effectiveness of eye-movements in EMDR.